#!/usr/bin/env python3

"""
Transform an unpaywall dump (JSON) into ingest requests.
"""

import sys
import json
import argparse
import urlcanon

DOMAIN_BLOCKLIST = [
    # large OA publishers (we get via DOI)

    # large repos and aggregators (we crawl directly)
    "://arxiv.org/",
    "://europepmc.org/",
    "ncbi.nlm.nih.gov/",
    "semanticscholar.org/",
    "://doi.org/",
    "zenodo.org/",
    "figshare.com/",
    "://archive.org/",
    ".archive.org/",
]

RELEASE_STAGE_MAP = {
    'draftVersion':     'draft',
    'submittedVersion': 'submitted',
    'acceptedVersion':  'accepted',
    'publishedVersion': 'published',
    'updatedVersion':   'updated',
}

def canon(s):
    parsed = urlcanon.parse_url(s)
    return str(urlcanon.whatwg(parsed))

def transform(obj):
    """
    Transforms from a single unpaywall object to zero or more ingest requests.
    Returns a list of dicts.
    """

    requests = []
    if not obj['doi'].startswith('10.'):
        return requests
    if not obj['oa_locations']:
        return requests

    for location in obj['oa_locations']:
        if not location['url_for_pdf']:
            continue
        skip = False
        for domain in DOMAIN_BLOCKLIST:
            if domain in location['url_for_pdf']:
                skip = True
        if skip:
            continue
        try:
            base_url = canon(location['url_for_pdf'])
        except UnicodeEncodeError:
            continue

        request = {
            'base_url': base_url,
            'ingest_type': 'pdf',
            'link_source': 'unpaywall',
            'link_source_id': obj['doi'].lower(),
            'ingest_request_source': 'unpaywall',
            'release_stage': RELEASE_STAGE_MAP.get(location['version']),
            'rel': location['host_type'],
            'ext_ids': {
                'doi': obj['doi'].lower(),
            },
            'edit_extra': {},
        }
        if obj.get('oa_status'):
            request['edit_extra']['oa_status'] = obj['oa_status']
        if location.get('evidence'):
            request['edit_extra']['evidence'] = location['evidence']
        if location['pmh_id']:
            request['ext_ids']['pmh_id'] = location['pmh_id']
        requests.append(request)

    return requests

def run(args):
    for l in args.json_file:
        if not l.strip():
            continue
        row = json.loads(l)

        requests = transform(row) or []
        for r in requests:
            print("{}".format(json.dumps(r, sort_keys=True)))

def main():
    parser = argparse.ArgumentParser(
        formatter_class=argparse.ArgumentDefaultsHelpFormatter)
    parser.add_argument('json_file',
        help="unpaywall dump file to use",
        type=argparse.FileType('r'))
    subparsers = parser.add_subparsers()

    args = parser.parse_args()

    run(args)

if __name__ == '__main__':
    main()